A polymer electrolyte fuel cell using a proton conductive solid polymer membrane operates at a low temperature in comparison to other types of fuel cells, for example, a solid oxide fuel cell or a molten carbonate fuel cell. For this reason, the polymer electrolyte fuel cell has been expected to be used as a power source for energy storage system or a driving power source for a vehicle such as a car, and practical uses thereof have been started.
In general, expensive metal catalysts such as Pt (platinum) and Pt alloys have been used for such a polymer electrolyte fuel cell. Also graphitized carbon has been used as a support for supporting a metal catalyst in terms of water repellency and corrosion resistance. For example, Patent Literature 1 discloses a technique using a support having an average lattice spacing of (002) plane, d002, of 0.338 to 0.355 nm, a specific surface area of 80 to 250 m2/g, and a bulk density of 0.30 to 0.45 g/ml. Patent Literature 1 discloses that durability can be improved by using the graphitized support.